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Lithium Hypochlorite Registration Review Team 

Human Health 

Jonathan Leshin 

Timothy Dole 

Environmental Fate and Effects 

William Erickson 

Srinivas Gowda 

Najm Shamim 

Risk Management 

Donna Kamarei 

Rose Kyprianou 

Wanda Henson 

Office of General Counsel 

Philip Ross 

 
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Table of Contents 

1 Introduction .......................................................................................................................... 5

1.1 Statutory and Regulatory Authority .............................................................................. 5

1.2 Case Overview ............................................................................................................... 6

1.3 Chemical Identification and Properties ......................................................................... 7

1.4 Use/Usage Description .................................................................................................. 8

1.4.1 Summary of Registered Uses ................................................................................. 8

1.5 Regulatory History ........................................................................................................ 9

1.5.1 Recent/Pending Regulatory Actions ...................................................................... 9

1.5.2 Tolerance Information ............................................................................................ 9

1.6 Incidents ......................................................................................................................... 9

1.6.1 Human Health ........................................................................................................ 9

1.6.2 Ecological ............................................................................................................... 9

2 Anticipated Data Needs ........................................................................................................ 9

3 Human Health Risk Assessment ........................................................................................ 10

3.1 Existing Toxicological Endpoints ............................................................................... 10

3.2 Dietary Exposure .............................................................................................................. 11

3.3 Occupational and Residential Exposures ......................................................................... 11

3.4 Aggregate and Cumulative Exposure ............................................................................... 11

4 Environmental Risk Assessment ........................................................................................ 11

4.1 Environmental Fate and Exposure Pathways .............................................................. 11

4.1.1 Water Quality ....................................................................................................... 12

4.2 Ecological Effects Assessment .................................................................................... 12

4.2.1 Mode of Action .................................................................................................... 12

4.2.2 Measures of Effect (Ecotoxicology Assessment Endpoints) ............................... 12

4.3 Exposure Analysis Plan ............................................................................................... 14

4.3.1 Aquatic and Terrestrial Wildlife Exposure Estimates .......................................... 14

5 Endocrine Disruptor Screening Program (EDSP) .............................................................. 14

6 Optional Label Changes ..................................................................................................... 15

7 Guidance for Commenters ................................................................................................. 15

7.1 Preliminary Work Plan ................................................................................................ 15

7.1.1 Trade Irritants ....................................................................................................... 16

7.1.2 Water Quality ....................................................................................................... 16

7.1.3 Environmental Justice .......................................................................................... 16

7.1.4 Structure Activity Relationships .......................................................................... 16

7.1.5 Additional Information ......................................................................................... 17

8 Next Steps .......................................................................................................................... 18

9 References .......................................................................................................................... 19
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Appendix A Toxicology Profile ...................................................................................................... 22

Appendix B Environmental Fate and Transport of Lithium Hypochlorite ..................................... 24

Appendix C Ecotoxicology Profile ................................................................................................. 27

Appendix D Product Chemistry ...................................................................................................... 30

List of Tables 

Table 1 – Summary of Anticipated Risk Assessments and Data Needs: Lithium Hypochlorite ...... 6

Table 2 – Anticipated Registration Review Schedule for Lithium Hypochlorite ............................. 6

Table 3 – Chemical Identification of Lithium Hypochlorite ............................................................. 7

Table 4 – Physical-Chemical and Environmental Fate Properties for Lithium Hypochlorite .......... 7

Table 5 – Summary of Lithium Hypochlorite Registered Uses ........................................................ 8

Table 6 – Available Ecological Effects Endpoints for the Ecological Assessment of Lithium 

Hypochlorite....................................................................................................13 

Table 7 – Acute Toxicity Data for Lithium Hypochlorite..............................................................22 

List of Figures 

None. 

 
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1 Introduction 

This document is the Environmental Protection Agency’s (EPA or “the agency”) Preliminary 

Work Plan (PWP) for lithium hypochlorite. The PWP document explains what EPA's Office of 

Pesticide Programs knows about lithium hypochlorite, highlighting anticipated data and 

assessment needs, identifying the types of information that would be especially useful to the 

agency in conducting the review, and providing an anticipated timeline for completing lithium 

hypochlorite’s review. 

The registration review process was designed to include a public participation component to solicit 

input from interested stakeholders. The agency intends, by sharing this information in the docket, 

to inform the public of what it knows about lithium hypochlorite and what types of new data or 

other information would be helpful for the agency to receive as it moves toward a decision on 

lithium hypochlorite. The agency encourages all interested stakeholders to review the PWP and to 

provide comments and additional information that will help the agency’s decision-making process 

for this chemical. 

1.1 Statutory and Regulatory Authority 

The Food Quality Protection Act (FQPA) of 1996 mandated a registration review program. All 

pesticides distributed or sold in the United States generally must be registered by the U.S. 

Environmental Protection Agency based on scientific data showing that they will not cause 

unreasonable risks to human health or the environment when used as directed on product labeling. 

The registration review program is intended to make sure that, as the ability to assess risk evolves 

and as policies and practices change, all registered pesticides continue to meet the statutory 

standard of no unreasonable adverse effects to human health or the environment. Changes in 

science, public policy, and pesticide use practices will occur over time. Through the registration 

review program, the agency periodically reevaluates pesticides to make sure that as change occurs, 

products in the marketplace can be used safely. Information on this program is provided at 

http://www.epa.gov/oppsrrd1/registration_review/. 

The agency is implementing the registration review program pursuant to Section 3(g) of the 

Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and will review each registered 

pesticide every 15 years to determine whether it continues to meet the FIFRA standard for 

registration. The regulations governing registration review begin at 40 CFR 155.40. The agency 

will consider benefits information and data as required by FIFRA. The public phase of registration 

review begins when the initial docket is opened for each case. The docket is the agency’s 

opportunity to state what it knows about the pesticide and what additional risk analyses and data 

or information it believes are needed to make a registration review decision. After reviewing and 

responding to comments and data received in the docket during this initial comment period, the 

agency will develop and commit to a Final Work Plan (FWP) and anticipated schedule for the 

lithium hypochlorite case. The agency may combine this case with sodium and calcium 

hypochlorite (case 0029). 

Documents associated with this registration review can be viewed at http://www.regulations.gov 

in docket EPA-HQ-OPP-2013-0606. Tables 1 and 2 below summarize the issues relevant to this 

registration review case and the anticipated registration review schedule. 
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Table 1 – Summary of Anticipated Risk Assessments and Data Needs: Lithium Hypochlorite 

Risk Assessment 

Assessment Necessary to 

Support Registration 

Review 

Date of Most Recent 

Assessment 

Type of 

Assessment 

Required 

(New/Updated) 

Data 

Anticipated 

as Needed 

Dietary (food) No (see section 3.2) None None None 

Dietary (drinking water) No (see section 3.2) None None None 

Occupational Handler No (see section 3.3) None None None 

Residential Handler No (see section 3.3) None None None 

Aggregate No (see section 3.4) None None None 

Cumulative No (see section 3.4) None None None 

Tolerance Review No (see section 1.5.2) None None None 

Ecological Yes December 1st, 1993 New 

(swimming pools) None 

Table 2 – Anticipated Registration Review Schedule for Lithium Hypochlorite 

Anticipated Activity Target Date* Completion Date

Phase 1: Opening the Docket 

Open Docket and 60-Day Comment Period for Preliminary Work Plan 2014-03 March 26, 2014 

Close Public Comment Period 2014-05 

Phase 2: Case Development 

Issue Final Work Plan 2014-09 

Issue Data Call-In (DCI) N/A 

Receive Data to be Considered in Risk Assessment N/A 

Open 30-Day Public Comment Period for Preliminary Risk Assessment(s) 2016-03 

Close Public Comment Period 2016-04 

Phase 3: Registration Review Decision and Implementation 

Open 60-Day Public Comment Period for Proposed Decision 2016-09 

Close Public Comment Period 2016-11 

Issue Final Decision 2017-03 

Begin Post-Decision Followup 2017 

Total (years) 3 

*The anticipated schedule will be revised as necessary (e.g., need arising under the Endocrine Disruptor Screening Program with 

respect to the active ingredients in this case). 

1.2 Case Overview 

The docket for the lithium hypochlorite case (case 3084) has been established at 

http://www.regulations.gov in docket number EPA-HQ-OPP-2013-0606. 
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1.3 Chemical Identification and Properties 

Table 3 presents the active ingredient to be assessed in case 3084: lithium hypochlorite (PC Code 

014702). 

Table 3 – Chemical Identification of Lithium Hypochlorite 

Chemical Name Lithium Hypochlorite 

Chemical Classification Halogen 

PC Code 014702 

CAS Number 13840-33-0 

Molecular Formula LiOCl 

Molecular Weight (grams/mole) 58.4 

Purity 29% LiOCl 

Available chlorine 35% 

Molecular Structure 

The lithium hypochlorite product chemistry information relevant to risk assessment is summarized 

in Table 4 (source: MRIDs 7257, 7258, 94669, 93138001, 42940801, 42967001, 42967002, 

42967003, 42991801, 31007-02, 31007-03, 5045001-15). 

Table 4 – Physical-Chemical and Environmental Fate Properties for Lithium Hypochlorite 

Guideline 

No. Parameter Lithium Hypochlorite (29%) 

Physical/Chemical Properties 

830.7000 pH 

9.9 (available Cl2 - 100 ppm) in dist. water at 25°C. 

10.3 (available Cl2 - 200 ppm) in dist. water at 25°C. 

10.7 (available Cl2 - 300 ppm) in dist. water at 25°C. 

11 at 25 °C (1% Solution) 

830.7050 UV/Visible Absorption Not reported 

830.7200 Melting point 135°C with decomposition 

830.7220 Boiling point (oC) Not applicable 

830.7300 Density 0.531 g/cm3

 (20 °C) 

Bulk Density: 58 lbs/ft3

830.7370 Dissociation constant (pKa) 3.2 x 10-8 (of HOCl in aqueous solution) 

830.7550 Octanol-water partition coefficient at 25 o

C 

(Log Kow) Not applicable 

830.7840 Solubility in water (mg/L) 43% by weight at 25°C 

830.7950 Vapor pressure (mmHg) 6.63 x 10-17 mm Hg (EPI Suite v 4.1) 

Environmental Fate Properties 

Henry's law constant at 25 oC (atm-m3/mol) Not applicable; very low vapor pressure ; inorganic 

substance 

Octanol-air partition coefficient at 25 oC (Log 

KOA) Not applicable 
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Guideline 

No. Parameter Lithium Hypochlorite (29%) 

Air-water partition coefficient (Log KAW) Not applicable 

Mobility 

 Organic Carbon Partitioning Coefficient (Koc) 

Persistence in Water (half-life) 

 Hydrolysis at 25 oC: pH 5, 7 & 9 (days) Not applicable; inorganic substance 

 Aqueous photolysis at 25 oC (days) Not applicable; inorganic substance 

 Aerobic aquatic metabolism (days) Not applicable; inorganic substance 

 Anaerobic aquatic metabolism half-life (days) Not applicable; inorganic substance 

Persistence in Soil (half-lifes) 

 Soil photolysis (days) Not applicable; inorganic substance 

 Aerobic soil metabolism at 25 oC (days) Not applicable; inorganic substance 

 Anaerobic soil metabolism (days) 

Persistence in WWTP (% removed) 

 [Ready biodegradation,....] Not applicable; inorganic substance 

atm-m3/mol = atmosphere cubic meter per mole; oC = degrees Celsius; mg/L = milligrams per liter; mmHg = 

millimeters of mercury. 

1.4 Use/Usage Description 

1.4.1 Summary of Registered Uses 

Lithium hypochlorite is registered for use as sanitizer/algaecide in swimming pools and as a 

sanitizer for spas/hot tubs. There are 18 end use products and they all contain 29 percent lithium 

hypochlorite (35 percent available chlorine). A listing of the registered uses of lithium 

hypochlorite is included in Table 5. 

Table 5 – Summary of Lithium Hypochlorite Registered Uses 

Use Application 

Method

Product Application 

Rate 

Lithium Hypochlorite 

Application Rate 

(ppm) 

Available Chlorine 

Application Rate 

(ppm) 

Swimming Pool Shock 

Treatment Open Pour 16 ounces/6000 gallons 5.8 7.0A 

Swimming Pool 

Maintenance Treatment Open Pour 3.7 ounces/6000 gallons 1.16 1.4 

Spa Shock Treatment Open Pour 1.0 ounce/250 gallons 8.8 10B

Spa Superchlorination 

Treatment Open Pour 0.5 ounce/250 gallons 4.4 5.3B

Spa Maintenance 

Treatment Open Pour 0.25 ounce/250 gallons 2.2 2.7 

A. Applications are made at least 12 hours prior to pool use. Rentry to the pool is not allowed until the chlorine level 

is below 3.0 ppm

B. Labels include statements such as “Do not enter spa until available chlorine residual falls to 3.0 or below.” 
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1.5 Regulatory History 

The first product containing lithium hypochlorite as an active ingredient was registered in 1963, 

and it has been used chiefly as a sanitizer in swimming pools. There are currently 18 end use 

products with lithium hypochlorite as an active ingredient. The agency completed a Reregistration 

Eligibility Decision (RED) for lithium hypochlorite in 1993. There are currently no outstanding 

Data Call-In (DCI) requirements for this active ingredient. 

1.5.1 Recent/Pending Regulatory Actions 

There are no pending regulatory actions for lithium hypochlorite. 

1.5.2 Tolerance Information 

There are no tolerances or exemptions from tolerances for lithium hypochlorite because there are 

no currently registered uses for this active ingredient associated with food or feed. 

1.6 Incidents 

1.6.1 Human Health 

There are a total of seven incidents listed in the OPP Incident Data System for the period 9/2001 

to the present (search conducted on 1/17/2014). Four of these incidents involved product misuse, 

such as over application of the product, use of the product with other chlorine sources, addition of 

the product to a bucket of water or use of the product on an unregistered site. One incident 

involved a fire in a warehouse where products were stored and another incident involved workers 

at a formulation facility who experienced respiratory irritation. 

There is one incident that occurred in 2005 where a swimmer allegedly experienced dermal 

irritation effects (hives, welts and pruritus) after swimming in a public pool treated with the 

product. The pool had been treated approximately one hour before the swimmer was exposed. 

1.6.2 Ecological 

There are no fish or wildlife poisoning incidents in OPP’s Incident Data System involving lithium 

hypochlorite as of January 22, 2014. 

2 Anticipated Data Needs 

The agency does not anticipate needing to call in any data to support this registration review. 

 
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3 Human Health Risk Assessment 

EPA does not anticipate the need to revise the existing toxicological endpoints as part of this 

registration review. The toxicological data base on lithium hypochlorite is adequate and will 

support this registration review case. 

3.1 Existing Toxicological Endpoints 

The primary toxicological consideration is the effect from exposure to the lithium ion that is 

produced from the reaction of lithium hypochlorite with water that produces hypochlorous acid 

and lithium ions. Hypochlorous acid (which is an oxidizing agent and the chemical species 

showing actual pesticidal activity) acts by oxidizing organic and inorganic chemical 

contaminants. As hypochlorous acid exerts its oxidizing effect, the chlorine reduces to chloride 

ions. Thus the end-products of lithium hypochlorite are chloride and lithium ions, both 

ubiquitous in the environment, and adverse effects from the incremental lithium hypochlorite 

contribution are not expected. Therefore this chemical will be evaluated qualitatively and 

toxicological endpoints will not be set.1

The average background level of lithium in human serum has been reported as 0.014 mg/L which 

comes primarily from the natural content of lithium in food and drinking water (MRID 

41367401). It has been estimated that the natural sources of lithium provide 2.3-4.9 mg/day of 

lithium. Lithium carbonate has been used as a human drug since about 1970. The intake levels 

are 179 to 282 mg/day of lithium ion and they provide about 4.16 to 8.33 mg/L of lithium in the 

serum (MRID 41367401). For the therapeutic use, the reported maximum no-toxicity levels are 

10.41 to 13.88 mg/L in serum. These levels are far higher than the background levels and higher 

than any expected from pesticide use of lithium hypochlorite (MRID 41367401). In addition, 

lithium orotate and lithium aspartate salts are sold as over-the-counter mineral supplements that 

provide about 5 mg of lithium per daily dose. Clinical and epidemiologic studies on human use 

of lithium-containing drugs, including chronic use, have not shown any reason for concern over 

continued human exposure to lithium at the low levels of exposure expected during the pesticidal 

use scenario (MRID 41367401). The EPA Hazard and Science Policy Council (HASPOC) 

assessed the need for acute neurotoxicity, subchronic neurotoxicity, immunotoxicity, chronic 

toxicity, carcinogenicity, and reproduction and fertility studies on December 12th, 2013 (TXR# 

0056855). Based on a weight of evidence approach considering all the available hazard and 

exposure information for lithium hypochlorite, the HASPOC concluded that the acute/subchronic 

neurotoxicity, immunotoxicity, chronic/cancer, subchronic inhalation, and reproduction and 

fertility are not required. 

Past lithium hypochlorite risk assessments have relied in part on the following two human 

studies which may have involved intentional exposure to lithium hypochlorite. In the course of 

registration review, EPA will reconsider these studies, as well as any other research involving 

intentional exposure of human subjects to lithium hypochlorite brought to its attention. If EPA 

 

1

 U.S. EPA 2012. Registration Review Final Work Plan: Na & Ca Hypochlorite. Docket Number EPA –HQ-OPP 

2012-0004.Available at: http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2012-0004-0006. 
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decides to rely on any of these studies, EPA will ensure that all applicable regulatory 

requirements are met, including but not limited to the requirements for EPA ethics review and 

Human Studies Review Board review of certain research involving intentional exposure of 

human subjects. 

3.2 Dietary Exposure 

There are no registered uses for lithium hypochlorite associated with food or feed, thus the 

registered uses of lithium hypochlorite are not anticipated to result in food exposures. In 

addition, there are no toxicological endpoints for lithium and thus dietary exposures from 

drinking water do not need to be assessed for registration review. 

3.3 Occupational and Residential Exposures 

Because there are no toxicological endpoints for lithium, occupational and residential exposures 

do not need to be assessed for registration review. 

3.4 Aggregate and Cumulative Exposure 

Because there are no toxicological endpoints for lithium, aggregate and cumulative exposures do 

not need to be assessed for registration review. 

4 Environmental Risk Assessment 

An ecological risk assessment for industrial discharge from food-processing plants and eating 

establishments was conducted for the RED (EPA, 1993). Using a screening model that assumed 

no environmental degradation, level of concerns were exceeded for fish and aquatic invertebrates 

for a high-exposure scenario. Those uses are not currently registered. Swimming pool use was 

not assessed for the RED, because no model was available to estimate the estimated 

environmental concerns in discharge water when pools are drained. The ecological risk 

assessment planned during registration review will allow the agency to determine potential acute 

and chronic risks to aquatic organisms exposed to lithium hypochlorite transported from 

antimicrobial use sites into the aquatic environment. 

The Agency has not previously conducted a risk assessment that supports a complete endangered 

species determination for lithium hypochlorite. The risk assessment will allow the agency to 

determine whether use of lithium hypochlorite has 'no effect' or 'may affect' federally listed 

threatened or endangered species (listed species) or their designated critical habitats. When an 

assessment concludes that a pesticide’s use 'may affect' a listed species or its designated critical 

habitat, the agency will consult with the U.S. Fish and Wildlife Service and/or National Marine 

Fisheries Services (the Services), as appropriate. 

4.1 Environmental Fate and Exposure Pathways 

Lithium hypochlorite belongs to the hypochlorite class of compounds including sodium, 

potassium and calcium hypochlorites. These hypochlorites rapidly dissociate in water to form 

hypochlorous acid (HOCl), which acts as the active in disinfection scenarios. 
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The agency has not conducted any environmental and transport exposure assessments for lithium 

hypochlorite. Lithium is a naturally occurring element and is often used in industrial settings 

Lithium chemistry is similar to group cations like sodium, potassium and calcium ions. All salts 

of these metals are highly water soluble.2

 

The agency anticipates needing to estimate surface water concentrations of Li ions from release 

from swimming pools and spas. 

4.1.1 Water Quality 

Lithium hypochlorite is not identified as a cause of impairment for any water bodies listed as 

impaired under section 303(d) of the Clean Water Act, based on information provided at the 

agency’s National Pesticides Cause of Impairment of Waters website (searched February 6, 

2014).3

 In addition, no Total Maximum Daily Loads (TMDL) have been developed for lithium 

hypochlorite, based on information provided at the agency’s National Pesticide TMDL website 

(searched February 6, 2014).4

 Lithium ions are not identified as a cause of impairment for any 

water bodies listed as impaired under section 303(d) of the Clean Water Act, based on 

information provided at the agency’s National Pesticides Cause of Impairment of Waters website 

(February 6, 2014).3

5

 There are 175 TMDL/ impaired water bodies (OW’s list 303(d)) listed for 

total residual chlorine (TRC) on a national level recorded between 2000-2007. TRC is defined 

as the “amount of remaining chlorine remaining after contact time and is equal to available 

residual chlorine + free available chlorine.” More information on impaired water bodies and 

TMDLs can be found at http://www.epa.gov/owow/tmdl/. 

4.2 Ecological Effects Assessment 

4.2.1 Mode of Action 

In the aquatic environment, toxic action is largely due to hypochlorous acid formed when lithium 

hypochlorite reacts with water. Adverse effects of hypochlorous acid are due mainly to its 

corrosive action. Acute necrosis may occur. Fish gills-structure may be damaged; gill necrosis 

can lead to respiratory problems and asphyxiation. The protective slime coating on fish also may 

be removed due to corrosive action (EPA 1985, Singleton and Bio 1989). 

4.2.2 Measures of Effect (Ecotoxicology Assessment Endpoints)

4.2.2.1 Submitted Data 

Ecological effects data are used as measures of direct and indirect effects to aquatic and 

terrestrial organisms. Acute and chronic toxicity data from registrant-submitted studies 

conducted in accordance with the 850 OCSSP Harmonized Test Guidelines (see Table 6) will be 

 

2

 F.A. Cotton & G. Wilkinson (Advanced Inorganic Chemistry, 7th edition; chapter 4 and 5). 3

http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885 

4

http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_id=885&p_pollutant_

group_name=PESTICIDES 

5

http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885 
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used to evaluate the potential direct and indirect effects of lithium hypochlorite to animals and 

plants. Additionally, as described below, relevant data from the EPA’s Office of Water and from 

the open literature also may be used to evaluate potential direct and indirect effects. 

All available ecotoxicity endpoints from studies submitted by registrants are tabulated and 

referenced in the Ecological Effects Profile (Appendix C). OPP uses the most sensitive of these 

endpoints for assessing acute and chronic risks to each aquatic receptor group. The avian 

toxicity endpoint is used to determine the need for precautionary labeling for hazards to wildlife. 

The Agency has a complete database to determine the effects of hypochlorous acid on aquatic 

organisms. The endpoints selected for the assessment for hypochlorous acid from the data 

submitted to the agency are provided in Table 6. 

Table 6 – Available Ecological Effects Endpoints for the Ecological Assessment of Lithium 

Hypochlorite 

 Receptor 

Group 

Test 

Material

Risk 

Scenario 

Toxicity Endpoint 

(TRC or CPO)a Reference 

Freshwater fish TGAI Acute LC50 = 200 μg ai/L 00094672 

Chronic -- None 

Freshwater invertebrates TGAI Acute EC50 = 230 μg ai/L 00094674 

Chronic -- None 

Estuarine/marine fish TGAI 

Acute -- None 

Chronic -- None 

Estuarine/marine 

invertebrates TGAI 

Acute -- None 

Chronic -- None 

Sediment-dwelling 

invertebrates TGAI Acute and Chronic -- None 

Algae TGAI 

EC50

NOAEC -- None 

Aquatic vascular 

 Plants TGAI EC50NOAEC -- None 

Birds TGAI Acute LD50 = mg ai/kg 00094673 

a

 Toxicity values are expressed as total residual chlorine (TRC) for freshwater organisms and as chlorine-produced 

oxidants (CPO) for seawater organisms (EPA 1985). 

4.2.2.2 Office of Water Data 

EPA’s Office of Water’s Ambient Water Quality Criteria for Chlorine4

6 provides additional data 

that will be used in the risk assessment. The document contains a review of open literature on 

acute and chronic effects of chlorine. Based on the available toxicological endpoints, freshwater 

and saltwater organism acute and chronic water quality criteria (expressed as total residual 

 

6

See EPA’s Office of Water’s Ambient Water Quality Criteria for Chlorine -1984(EPA, 1985) at: 

http://water.epa.gov/scitech/swguidance/standards/upload/2001_10_12_criteria_ambientwqc_chlorine1984.pdf 
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chlorine (TRC) for freshwater and chlorine-produced oxidants (CPO) for seawater) are derived. 

The current values are as follows: 

 Freshwater Criterion Maximum Concentration = 19 μg/L; 

 Freshwater Criterion Continuous Concentration = 11 μg/L; 

 Saltwater Criterion Maximum Concentration = 13 μg/L; and 

 Saltwater Criterion Continuous Concentration = 7.5 μg/L 

4.2.2.3 Open Literature 

The agency is aware of reviews of ecotoxicity data for lithium which will be obtained from the 

open literature for the risk assessment of lithium ions and salts. No data have been submitted to 

determine the toxicity of the lithium ion; therefore, the open literature will be evaluated to 

determine the potential for its toxicity when the risk assessment is conducted. 

Open literature studies also will be obtained via EPA’s ECOTOXicology (ECOTOX) database. 

The ECOTOX database will be searched when the risk assessment is prepared. Any acute or 

chronic endpoints more sensitive than what is currently available will be used in the risk 

assessment and risk characterization. Any relevant ecotoxicity data on the lithium ion also will 

be used. The Evaluation Guidelines for Ecological Toxicity Data in the Open Literature are 

discussed in more detail on the agency’s website at 

www.epa.gov/pesticides/science/efed/policy_guidance/team_authors/endangered_species_reregi

stration_workgroup/esa_evaluation_open_literature.htm. 

4.3 Exposure Analysis Plan 

4.3.1 Aquatic and Terrestrial Wildlife Exposure Estimates 

The agency is currently developing an assessment method to provide estimates of exposure for 

pesticides applied to swimming pools and potentially released into the environment when pools 

are drained. The agency anticipates using all available information when the risk assessment is 

conducted for lithium hypochlorite. 

5 Endocrine Disruptor Screening Program (EDSP) 

As required by FIFRA and FFDCA, EPA reviews numerous studies to assess potential adverse 

outcomes from exposure to chemicals. Collectively, these studies include acute, subchronic and 

chronic toxicity, including assessments of carcinogenicity, neurotoxicity, developmental, 

reproductive, and general or systemic toxicity. These studies include endpoints which may be 

susceptible to endocrine influence, including effects on endocrine target organ histopathology, 

organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, 

and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and 

chronic studies that assess growth, developmental and reproductive effects in different 

taxonomic groups. As part of its 1993 reregistration decision for lithium hypochlorite, EPA 

reviewed these data and selected the most sensitive endpoints for relevant risk assessment 

scenarios from the existing hazard database. However, as required by FFDCA section 408(p), 
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lithium hypochlorite is subject to the endocrine screening part of the Endocrine Disruptor 

Screening Program (EDSP). 

EPA has developed the EDSP to determine whether certain substances (including pesticide 

active and other ingredients) may have an effect in humans or wildlife similar to an effect 

produced by a “naturally occurring estrogen, or other such endocrine effects as the Administrator 

may designate.” The EDSP employs a two-tiered approach to making the statutorily required 

determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a 

chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or T) hormonal 

systems. Chemicals that go through Tier 1 screening and are found to have the potential to 

interact with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPA 

will determine which, if any, of the Tier 2 tests are necessary based on the available data. Tier 2 

testing is designed to identify any adverse endocrine-related effects caused by the substance, and 

establish a dose-response relationship between the dose and the E, A, or T effect. 

Under FFDCA section 408(p), the agency must screen all pesticide chemicals. Between October 

2009 and February 2010, EPA issued test orders/data call-ins for the first group of 67 chemicals, 

which contains 58 pesticide active ingredients and 9 inert ingredients. A second list of chemicals 

identified for EDSP screening was published on June 14, 20135

7

 and includes some pesticides 

scheduled for registration review and chemicals found in water. Neither of these lists should be 

construed as a list of known or likely endocrine disruptors. 

For further information on the status of the EDSP, the policies and procedures, the lists of 

chemicals, future lists, the test guidelines and the Tier 1 screening battery, please visit our 

website.86

6 Optional Label Changes 

The agency invites comment on any label amendments that could be considered to reduce the 

possibility that EPA’s planned risk assessments overestimate risk due to reliance on conservative 

assumptions, and/or improve label clarity. 

7 Guidance for Commenters 

7.1 Preliminary Work Plan 

The public is invited to comment on EPA’s Preliminary Work Plan and rationale. The agency 

will carefully consider all comments as well as any additional information or data provided in a 

timely manner prior to issuing a final work plan for the lithium hypochlorite registration review 

case. 

 

7

 See http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPPT-2009-0477-0074 for the final second list of 

chemicals. 

8

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7.1.1 Trade Irritants 

Through the registration review process, the agency intends to solicit information on trade 

irritants and, to the extent feasible, take steps toward facilitating irritant resolution. The agency 

will work to harmonize tolerances and international maximum residue limits (MRLs) and may 

modify tolerance levels to do so, when possible. Stakeholders are asked to comment on any trade 

irritant issues resulting from lack of MRLs or disparities between U.S. tolerances and MRLs in 

key export markets, providing as much specificity as possible regarding the nature of the 

concern. 

7.1.2 Water Quality 

The agency invites submission of water quality data for this pesticide. To the extent possible, 

data should conform to the quality standards in Appendix A of the OPP Standard Operating 

Procedure: Inclusion of Impaired Water Body and Other Water Quality Data in OPP’s 

Registration Review Risk Assessment and Management Process7

9 in order to ensure they can be 

used quantitatively or qualitatively in pesticide risk assessments. 

7.1.3 Environmental Justice 

EPA seeks to achieve environmental justice, the fair treatment and meaningful involvement of all 

people, regardless of race, color, national origin, or income, in the development, implementation, 

and enforcement of environmental laws, regulations, and policies. To help address potential 

environmental justice issues, the agency seeks information on any groups or segments of the 

population who, as a result of their location, cultural practices, or other factors, may have 

atypical, unusually high exposure to lithium hypochlorite compared to the general population. 

Please comment if you are aware of any sub-populations that may have atypical, unusually high 

exposure compared to the general population. 

7.1.4 Structure Activity Relationships 

EPA must rely upon information of appropriate quality and reliability for each decision made by 

the agency. In the Office of Pesticide Programs (OPP), the evaluation process for a pesticide 

chemical traditionally begins with the applicant’s submission of a set of studies conducted with 

the specific pesticide chemical of interest. The use of the results of such testing (measured data) 

is a logical, scientifically rigorous process that identifies the physical, chemical, and 

environmental fate properties of the pesticide, as well as the dose and endpoints at which an 

adverse effect can occur in various animal species. 

Today, there is significant interest in alternative techniques, i.e., techniques other than data 

generation that could significantly inform the agency’s decision-making process. Recently, OPP 

has made increasing use of structure activity relationship (SAR) as part of its regulatory 

decision-making process. In the SAR process, a chemical's molecular structure is compared to 

that of other chemicals for which data are available. These structural similarities are then used to 

make predictive judgments about a chemical’s physical, chemical, and biological properties. 

Thus, the chemical’s physical, chemical, and biological properties are a function of (or directly 

 

9

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related to) the chemical’s molecular structure. Quantitative SAR is referred to as QSAR. To 

develop a QSAR, a selected set of measured data on a single physical, chemical, or biological 

property is used to derive a model (an equation) to predict the value of that property. 

Since SAR assessments and QSAR modeling are another set of tools that are available to Agency 

scientists, OPP has begun a process shift that envisions shifting from the current study-by-study 

approach to an approach in which the use of predicted data, generated using validated models, is 

considered along with information from open literature and studies specifically generated under 

Part 161 requirements. All relevant information would be considered as part of a weight-of-theevidence evaluation. 

At this time, EPA believes that for certain endpoints, especially physical/chemical and fate 

properties, that SAR and QSAR might be effectively utilized to fulfill these data requirements 

for many antimicrobial pesticide chemicals. When considering biological properties, at this time, 

EPA believes that SAR and QSAR can be most effectively utilized in the evaluation of 

chemicals that exhibit lower toxicity for human health and/or ecotoxicity parameters. This is 

appropriate because the risk assessment for lower toxicity chemicals can be stream-lined, i.e., a 

screening-level assessment procedure rather than multiple tiers of assessments with progressively 

more data requirements. 

If stakeholders believe that submission of predicted data can fulfill one of the data needs for the 

lithium hypochlorite case, then the agency invites submission of this information. The submitter 

would be expected to supply a rationale describing the utility of the information and provide 

documentation on the scientific validity of the information. The determination that the predicted 

data fulfills the data requirement would be at the sole discretion of the agency. Pre-submission 

consultation with the agency is encouraged. 

7.1.5 Additional Information 

Stakeholders are also specifically asked to provide available information and data that will assist 

the agency in refining its risk assessments, including any species-specific ecological effects 

determinations. The agency is interested in receiving the following information: 

1. Confirmation on the following label information: 

A. Sites of application 

B. Formulations 

C. Application methods and equipment 

D. Maximum application rates 

E. Frequency of application, application intervals and maximum number of 

applications 

F. Geographic limitations on use 

2. Use or potential use distribution 

3. Use history 

4. Usage/use information for non-agricultural uses (e.g., materials preservation) 

5. Typical application interval 

6. State or local use restrictions 
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7. Ecological incidents (non-target plant damage and avian, fish, reptilian, amphibian and 

mammalian mortalities) not already reported to the agency 

8. Monitoring data 

8 Next Steps 

After the 60-day comment period closes in May 2014, the agency will review and respond to any 

comments received in a timely manner, and then issue a Final Work Plan for the lithium 

hypochlorite case. 

 
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9 References 

00037615 Nelli, J. R. The Build-up of Lithium Ion in Swimming Pool Waters and Its 

Effect on Swimmers. (1964) Unpublished study submitted by Lithium Corp of 

America. 

00234351 a. Acute Oral Toxicity Study in Rats. (1977) Unpublished study prepared by 

Hazleton and submitted by Lithium Corp. of America. Study No. 668-103. 

b. Acute Dermal Toxicity Study in Rabbits. (1977) Unpublished study 

prepared by Hazleton and submitted by Lithium Corp. of America. Study No. 

668-104. 

c. Primacy Skin Irritation Study in Rabbits. (1977) Unpublished study prepared 

by Hazleton and submitted by Lithium Corp. of America. Study No. 668-105. 

d. Acute Eye Irritation Potential Study in Rabbits. (1977) Unpublished study 

prepared by Hazleton and submitted by Lithium Corp. of America. Study No. 

668-106. 

00252294 Guinea Pig Maximization Test with Lithcoa Lithium Hypochlorite (1984) 

Unpublished study prepared by Hazleton. Study No. 668/115. 

40545701 Yang, L. (1988) CHO/HGPRT Mutation Assay: 11945 Lithium Hypochlorite 

Study No. T5674.332005. Unpublished study prepared by Microbiological 

Associates Inc. 30 p. 

40545702 Batt, K. (1987) Salmonella/Mammalian-Microsome Plate Incorporation 

Mutagenicity Assay (Ames Test): Study No. 187-0975. Unpublished study 

prepared by FMC Corp., Genetic Toxicology Laboratory. 33 p. 

40545703 Putman, D. (1988) Chromosome Aberrations in Chinese Hamster Ovary 

(CHO) Cells: 11945 Lithium Hypochlorite I : Study No. T5674. 337020. 

Unpublished study prepared by Microbiological Associates, Inc. 29 p. 

40545704 Curren, R. (1988) Unscheduled DNA Synthesis in Rat Primary 

Hepatocytes:11945 Lithium Hypochlorite I :Final Report: T5674.380017. 

Unpublished study prepared by Microbiological Associates, Inc. 28 p. 

40648101 Lochry, E. (1988) Developmental Toxicity (Embro/Fetal Toxicity and 

Teratogenic Potential) Study of Lithium Hypochlorite Administered Orally via 

Gavage to Crl:CD(SD)BR Presumed Pregnant Rats: Sponsor's Study No.187-

0978. Unpublished study prepared by Argus Research Laboratories, Inc. 236p. 

40746701 McCarty, J.; Carter, S.; Fletcher, M.; et al. (1988) Study of Lithium 

Absorption by Users of Spas Treated with Lithium Ion: Study No. 187-0981. 

Unpublished study prepared by FMC Toxicology Dept. 225 p. 
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Page 20 of 31

40803901 Freeman, C. (1988) Lithium Hypochlorite: Acute Oral Toxicity Study in Rats: 

Study No. 187-0982. Unpublished study prepared by FMC Toxicology 

Laboratory. 47 p. 

41367401 Todhunter, J.; Mandava, N. (1990) Supplemental Data and Documentation in 

Support of Data Waiver Requests filed by Lithium Corporation of America 

dated November 24, 1989: FMC Study No. I90-1108. Unpublished study 

prepared by SRS International. 1424 p. 

44643001 Signorin, J. (1998) Lithium hypochlorite commercial: Acute inhalation 

toxicity study in rats: Study No. 198-225. Unpublished study prepared by 

FMC Toxicology Laboratory. 70p. 

7257 Lithium Corporation of America (1969) Analysis of Lithium hypochlorite. 

Includes R & D method no. 210 dated Nov 1969. (Unpublished study received 

Dec 29, 1972 under 7675-1; CDL: 008072-A) 

7258 Lithium Corporation of America Product Information: LCA Lithium 

hypochlorite: Data Sheet 111-463. (Unpublished study received Aug 28, 1964 

under 7675-2; CDL:008073-A) 

94669 Lithium Corporation of American (1977) Storage Stability Data for Lithcoa 

Lithium Hypochlorite. (Unpublished study received Aug 24, 1979 under 7675-

4; CDL:246731-B) 

93138001 Cinq-Mars, R. (1990) Lithium Corporation of America Phase 3 Summary of 

MRID 00051222 and Related MRIDs 00007258, 00031511, 00094670, 

00007261, 00094669, 00094670. Chemical and Physical Properties of Lithium 

Hypochlorite. 34 p. 

42940801 Hatch, H. (1993) Beginning Materials and Manufacturing Process: FIFRA 

Reregistration of Lithium Hypochlorite: Product Class-C: Data Gaps in Phase 

III Submission. Unpublished study. 18 p. 

42967001 Hatch, H. (1993) FIFRA Reregistration of Lithium Hypochlorite, Product 

Class-C: (Response to) Data Gaps in Phase III Submission: Solubility. 

Unpublished study prepared by FMC Corp. 7 p. 

42967002 Hatch, H. (1993) FIFRA Reregistration of Lithium Hypochlorite, Product 

Class-C: (Response to) Data Gaps in Phase III Submission: Vapor Pressure. 

Unpublished study prepared by FMC Corp. 4 p. 

42967003 Hatch, H. (1993) FIFRA Reregistration of Lithium Hypochlorite, Product 

Class-C: (Response to) Data Gaps in Phase III Submission: Dissociation 

Constant. Unpublished study prepared by FMC Corp. 10 p. 
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42991801 Eschbach, J. (1993) Method Validation and Determination of Lithco Lithium 

Hypochlorite for Swimming Pool/Spa Sanitation and Algea (sic) Control. 

Final Report: Lab Project Number: 93/9078: P93/0035. Unpublished study 

prepared by Pharmaco-LSR. 55 p. 

EPA. 1985. Ambient Water Quality Criteria for Chlorine - 1984. Regulations 

and Standards, Criteria and Standards Division, Office of Water, Washington, 

DC. 

Singleton, H.J. and R.P. Bio. 1989. Ambient Water Quality Criteria for Chlorine 

Technical Appendix. Resource Quality Section, Water Management Branch, 

Ministry of Environment, province of British Columbia, Victoria, B.C. 
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Appendix A Toxicology Profile 

Acute Toxicity for Product Labeling 

As summarized in Table 1, in acute toxicity studies, lithium hypochlorite has been shown to have 

data from an acute oral toxicity study in rats indicated LD50 of 748 mg/kg for males and 555

mg/kg for females. This study, which used technical lithium hypochlorite, indicates category III 

toxicity (MRID 40803901). A second acute oral toxicity study (MRID 234351) in rats that was 

conducted only in male animals is useful for indicating the nature of the observed effects. The 

effects in the rats were primarily due to the corrosive nature of the substance and included 

inflamed gastric mucosa and lungs, distended stomach, congested kidneys, yellow purulent 

material in chest cavity, and labored respiration. The oral LD50 for males in this study was 286 

mg/kg. The dermal LD50 was approximately 8100 mg/kg for female and male rabbits, which is 

category IV toxicity (MRID 234351). The inhalation LC50 was 1.8 mg/L for males, 2.1 mg/L for 

females, which combines to 2.0 mg/L LC50, which indicates category III toxicity (MRID 

44643001). The effects were dermal necrosis, severe erythema, anorexia, depression, and lack of 

body fat. The corrosive nature of lithium hypochlorite puts this compound in toxicity category I 

for both eye irritation and dermal irritation. A dermal sensitization study, which used solid 

lithium hypochlorite as a 10% solution in saline, did not demonstrate any dermal sensitization 

(MRID 252294). 

Table 7 – Acute Toxicity Data for Lithium Hypochlorite 

Guideline 

No. 

Data Requirement/ 

Species 

Conclusions/Acceptable/ 

Comments 

Tox 

Cat 

MRID 

870.1100 Acute oral toxicity - 

Rat 

746 mg/kg males 

555 mg/kg females 

III 40803901 

870.1200 Acute dermal 

toxicity - Rabbit 8100 mg/kg both sex IV 234351 

870.1300 Acute inhalation 

toxicity 

1.8 mg/L males 

2.1 mg/L females 

2.0 mg/L combined 

III 44643001 

870.2400 Acute eye irritation - 

Rabbit Severe irritation 

I 234351 

870.2500 Acute dermal 

irritation – Rabbit Severe irritation 

I 234351 

870.2600 Skin sensitization – 

Guinea pig Not sensitizing N.A. 252294 

 
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Subchronic Toxicity 

Subchronic inhalation studies were waived by the HASPOC (TXR # 0056855). As indicated by 

study MRID 40746701, there is no significant absorption of lithium through the intact skin and 

thus no long term dermal exposure risk. Subchronic oral studies are not considered required as 

all oral exposure is considered below normal ingestion via food and water. 

Developmental Toxicity 

In a developmental toxicity study four groups of 25 female rats were given, by gavage, lithium 

hypochlorite on gestation days six through fifteen (MRID 40648101) with one additional group 

of 25 rats as control. The dose levels were 0, 10, 50, 100, or 500 mg/kg/day using 30% test 

substance in water. The maternal and developmental NOELs were 100 mg/kg/day of lithium 

hypochlorite, which is equivalent to 4.1 mg/kg/day of lithium. The maternal LOBL was at 500 

mg/kg/day, based on deaths, reduced weight gain, reduced food consumption, and inflamed and 

congested respiratory system. The developmental LOEL was also at 500 mg/kg/day, where the 

fetuses showed reduced fetal weight, dilated renal pelvis, bifid vertebrae, wavy ribs, and 

unossified foot bones. A survey of animal studies in the published literature (MRID 41367401) 

generally found the no-effect levels at or above 4.5 mg/kg/day of lithium. None of the studies 

showed developmental effects at levels below those which showed maternal toxicity. 

Reproductive Toxicity 

These studies were waived by the HASPOC (TXR # 0056855). 

Chronic Toxicity and Carcinogenicity 

These studies were waived by the HASPOC (TXR # 0056855). 

Mutagenicity 

Technical lithium hypochlorite was negative, with and without metabolic activation, in an Ames 

test for mutagenicity using five strains of Salmonella (MRID 40545702). A study of unscheduled 

DNA synthesis in rat hepatocytes using technical lithium hypochlorite was also negative (MRID 

40545704). Lithium hypochlorite was negative in the CHO/HGPRT mutation assay with and 

without activation (MRID 40545701). A test for chromosome aberration in CHO cells with 

technical lithium hypochlorite was positive (MRID 40545703). However, a test for chromosomal 

aberrations in rat bone marrow cells was negative with lithium hypochlorite (MRID 40907500). 

Metabolism 

The lithium ion is rapidly absorbed after ingestion and is distributed through the body. It is 

excreted by the kidney and most of the ion is excreted within 6-8 hours after ingestion (MRID 

00037615). 

Other Toxicological Effects 

The immunotoxicity study was waived by the HASPOC (TXR # 0056855). 
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Appendix B Environmental Fate and 

Transport of Lithium Hypochlorite 

For inorganic-like hypochlorites, it is important to understand the speciation of these actives in 

the environmental medium like water to be able to determine risk concerns. All other parameters 

remaining constant (temperature, redox potential etc.), the pH changes vs. the speciation process 

becomes a very important fate factor for hypochlorite as seen below. 

pH profile of hypochlorite: 

It has been estimated the changes due to protolysis (hydrolysis) of a solution containing OCl- can 

be represented by the pH profile. The numerical data on the percent of HClO and ClO-

 from pH 

4 to 11 as shown below: 

pH 4 100% HClO 

pH 6.3 95% HClO/ 5% ClOpH 7.2 70% HClO / 30% ClOpH 7.7 50% HClO/ 50% ClOpH 8.0 21% HClO/ 79% ClOpH 11 100% ClOThe data above indicates that it is the OCl-

 and HOCl moieties that are the actives in the alkali 

hypochlorite (Na, K, Ca, and Li) systems under environmental conditions between pH 4 and 11. 

However, under different pH condition other moieties are present as indicated in the diagrams 

shown below.108

Versatility of chlorine and oxygen reactions: 

Chlorine is one the most versatile elements, particularly in regards to its reaction with oxygen. 

Chlorine shows numerous oxidation states (states of reactivity, from + 7 to -1). The following 

diagrams illustrate a number of facts: a) from the highest oxidation state in ClO4

-

 of + 7 to -1 in 

Cl- the reduction potentials are such that the reactions take place spontaneously in acidic or basic 

aquatic medium; b) The reverse reactions such as Cl- to ClO4

-

 are not spontaneous. 

 

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10 U.S. EPA 2012. Registration Review Final Work Plan: Na & Ca Hypochlorite. Docket Number EPA –HQ-OPP2012-0004.Available at: http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2012-0004-0006. 
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Under acidic conditions: 

ClO4

-  ClO3-

  ClO2

-  HClO2  HOCl  Cl2  Cl-

 

1 2 3 4 5 6 7 

 

Where: 

1 = perchlorate ion; 2= chlorate ion; 3= chlorite ion; 4= chlorous acid; 5= hypochlorous acid 

6= chlorine; 7= chloride ion 

Note: the oxidation state of chlorine in 1 = +7 and oxidation state in 7 = -1 

Under basic conditions: 

ClO4

-

  ClO3

-

  ClO2  ClO2

-  OCl-  Cl2  Cl-

 

1 2 3’ 4 5’ 6 7 

Where 3’= chlorine dioxide and 5’ = hypochlorous ion

It is not expected that hypochlorite will convert into highly oxidized species under the present 

use conditions. Thus depending on the pH, and oxidizing and reducing conditions in the 

environmental media, hypochlorite goes through speciation.119

Lithium element belongs to the alkali group of metals in the periodic table. Lithium is the 

smallest atom in the group and forms the smallest cation (Li+) after hydrogen ion. The aquatic 

chemistry of lithium salts is similar to sodium and potassium salt: chlorides, oxides, hydroxides, 

carbonates, and hypochlorites are highly soluble in water. Lithium reacts with organics to form 

organolithum substances. It is present in soils and sediments as a background mineral not as 

complexes but as salts.1210

In its Hazard Substance Database (HSDB), TOXNET has listed an Environmental Fate/Exposure 

Assessment.11

13 It is summarized here: 

Lithium is present in earth’s crust at an estimated level of 20-70 ppm by wt. It is widely 

distributed in the natural environmental media like minerals, rocks, soils, and natural waters and 

in many mineral springs. It sorbs to humic acids with a Koc1412 of about 4.6, which makes it mobile 

from humic acid surfaces. Because of its many uses, including the present use as a sanitizer in 

swimming pools and spas, lithium is released to the environment through many waste streams. 

It is non-volatile and is likely to exist in particulate forms in these matrices. In aquatic medium, 

it absorbs to the suspended soils and sediment (measured Kf 14 values ranged 4.5 to 5.5, which 

 

9

11 U.S. EPA 2012. Registration Review Final Work Plan: Na & Ca Hypochlorite. Docket Number EPA –HQ-OPP2012-0004.Available at: http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2012-0004-0006. 

10

12 F.A. Cotton & G. Wilkinson (Advanced Inorganic Chemistry, 7th edition; chapter 4 and 5). 13http:/pubchem.ncbi.nih.gov/toc/summary_toc.cgi?tocid=351&sid=96024823 5 55 

14Kf is the Freundlich adsorption coefficient for whole sediment. Koc is the Kf/% organic carbon 
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makes it loosely bound to such surfaces. Essentially lithium ions will be partitioned from soils 

and sediments to aqueous medium. Other possible pathways for lithium ion to be part of such 

environmental media are: to precipitate, or go through ligand exchange (e.g. sodium substitution 

for lithium). It is not likely to bioconcentrate as it is an ion. 

A few studies conducted on ground water on 118 sites in Western San Joaquin Valley, CA 

lithium concentrations was measured between 50 to 190 μg/l, during spring period; in 

Connecticut , the lithium was detected in 31/83 sample wells, with a median lithium 

concentration of < 4.0 μg/L. 

Measurements of lithium were taken in various US lakes, and waterways like Great Lakes basin, 

Lake Superior and Lake Michigan, Lake Erie/ green river, and the amounts varied depending on 

the anthropogenic use levels in these areas. 

A number of studies were conducted to estimate lithium ion concentration in drinking water . In 

94 large cities of US, the drinking water contained an average of 1.9 μg/L of lithium. In A 

Venezuelan Andes, the amounts were in the range of 5 to 80 μg/L. 

Lithium is found in onions, grapefruit in Texas, California, etc.; in orange from Florida. Lithium 

has been detected in leguminous plants. Lithium has been detected in various aquatic organisms 

like, cod, and mussels. 

There are no current federal standards for lithium in drinking water; average lithium intake is 2 

mg/day.13

15 

 

15 https://www.vdh.virginia.gov/Epidemiology/DEE/.../pdf/lithium.pdf 
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Appendix C Ecotoxicology Profile 

Toxicity to Terrestrial Organisms 

Birds 

An acceptable acute-oral (LD50) study categorizes lithium chlorite as being moderately toxic to 

birds. The guideline for an acute-oral test (850.2100) is satisfied. Dietary studies (850.2200) are 

not required. However, four dietary studies have been submitted and indicate that lithium 

chlorite is practically nontoxic to birds when administered in the diet. No additional data avian 

toxicity data are anticipated to be needed. 

Avian Acute-oral and Dietary Toxicity

Test Species Test Material 

(% ai) Toxicity Toxicity Category

EPA Study 

ID

Mallard 

(Anas platyrhynchos) 

29 LD50 = 567 mg ai/kg bw Moderately toxic 00094673 

Acceptable

29 LC50 >5000 ppm Practically nontoxic 00104674 

Acceptable 

15 LC50 >10,000 ppm Practically nontoxic 00104674 

Supplemental 

Northern bobwhite 

(Colinus virginianus) 

29 LC50 >5000 ppm Practically nontoxic 00104674 

Acceptable 

15 LC50 >10,000 ppm Practically nontoxic 00104674 

Supplemental 

Nontarget Insects 

Toxicity data for beneficial insects (850.3020, 850.3030) are not anticipated to be required for 

the use patterns of lithium hypochlorite, because lithium hypochlorite is not registered as a wood 

preservative. 

Toxicity to Aquatic Organisms 

Freshwater Fish 

The available acute toxicity studies categorize lithium hypochlorite as being moderately to 

highly toxic to freshwater fish. The guideline (850.1075) for acute toxicity testing is satisfied. 

No chronic data (fish early-life stage, 850.1400) are available. However, the need for chronic 

toxicity data can be fulfilled from EPA’s Office of Water’s Ambient Water Quality Criteria for 

Chlorine - 1984 (EPA 1985). No additional fish toxicity data are anticipated to be needed. 
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Acute Toxicity to Freshwater Fish

Test Species Test Material 

(% ai) 

Toxicity Endpoint 

(μg ai/L) 

Toxicity 

Category 

EPA Study 

ID 

Rainbow Trout 

(Oncorhynchus mykiss) 29 96-hr LC50 = 200 Highly toxic 00094672 Acceptable

15 96-hr LC50 = 2500 Moderately toxic 00007302 

Supplemental 

Bluegill 

(Lepomis macrochirus) 29 96-hr LC50 = 280 Highly toxic 00094672 

Acceptable 

15 96-hr LC50 = 6170 Moderately toxic 00007302 

Supplemental 

Freshwater Invertebrates 

The acute toxicity study for the waterflea categorizes lithium hypochlorite as being very highly 

toxic to freshwater invertebrates. The guideline (850.1010) for acute toxicity testing is satisfied. 

No chronic data (life-cycle, 850.1300) are available. However, the need for chronic toxicity data 

can be fulfilled from EPA’s Office of Water’s Ambient Water Quality Criteria for Chlorine - 

1984 (EPA 1985). No additional aquatic invertebrate toxicity data are anticipated to be needed. 

Toxicity to Freshwater Invertebrates

Test Species Test Material 

(% ai) 

Toxicity Endpoint 

(μg ai/L) 

Toxicity 

Category 

EPA Study 

ID 

Waterflea 

(Daphnia magna) 29 48-hr EC50 = 230 Very highly toxic 

00094674 

Acceptable 

Estuarine/Marine Fish and Invertebrates 

No acute or chronic data are available. Acute toxicity studies needed for the TGAI include tests 

for a fish sp. (850.1075), a bivalve sp. (850.1025 or 850.1055), and one additional invertebrate 

sp. (850.1035); to address these needs, the agency anticipates using the available data from 

EPA’s Office of Water’s Ambient Water Quality Criteria for Chlorine - 1984 (EPA 1985). 

Aquatic Plants 

No data are available. Studies needed for the TGAI include a toxicity test with a vascular species 

(850.4400), toxicity tests (850.4500) with 3 algal species (green algae, freshwater diatom, marine 

diatom), and a toxicity test using cyanobacteria (850.4550); to address these needs, the agency 

anticipates using the available data from EPA’s Office of Water’s Ambient Water Quality 

Criteria for Chlorine - 1984 (EPA 1985). 

Sediment toxicity 

Based on the environmental-fate properties of lithium hypochlorite (see section 4.1), lithium 

hypochlorite is not anticipated to accumulate in sediments. Therefore, sediment toxicity data are 

not anticipated to be required. 
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Appendix C References 

94673 Piccirillo, V.J. (1977) Final Report: Acute Oral LDI50 Study in Mallard Ducks: Project 

No. 668-107. (Unpublished study received Apr 25, 1978 under 7675-4; prepared by 

Hazleton Laboratories America, Inc. and Truslow Farms, Inc., submitted by Lithium 

Corp. of America, Gastonia, N.C.; CDL:246732-D) 

104674 Piccirillo, V.J. (1977) Final Report: Subacute Dietary LCI50 Study in Bobwhite Quail: 

Project No. 668-109. (Unpublished study received Apr 25, 1978 under 7675-4; prepared 

by Hazleton Lab- oratories America, Inc. and Truslow Farms, Inc., submitted by 

Lithium Corp. of America, Gastonia, N.C.; CDL:246732-B) 

94672 Buccafusco, R.J. (1978) Acute Toxicity of Lithcoa Lithium Hypochlorite to Rainbow 

Trout (Salmo gairdneri): Report #BW-78- 2-031. (Unpublished study received Apr 25, 

1978 under 7675-4; prepared by EG & G Bionomics, submitted by Lithium Corp. of 

America, Gastonia, N.C.; CDL:246732-C) 

7302 Sleight, B.H., III (1972) Bioassay Report: Acute Toxicity of K-70 Algaecide to Bluegill 

(Lepomis macrochirus) and Rainbow Trout (Salmo gairdneri). (Unpublished study 

received Dec 12, 1972 under 5135-17; prepared by Bionomics, Inc., submitted by 

Water Services, Burbank, Calif.; CDL:132135-C) 

94674 LeBlanc, G.A. (1978) Acute Toxicity of Lithcoa Lithium Hypochlorite to the Water 

Flea (Daphnia magna): Report #BW-78-2-032. (Unpublished study received Apr 25, 

1978 under 7675-4; prepared by EG & G Bionomics, submitted by Lithium Corp. of 

America, Gastonia, N.C.; CDL:246732-E) 

 
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Page 30 of 31

Appendix D Product Chemistry

Lithium hypochlorite product chemistry information is summarized in Table D1 (source: MRIDs 

7257, 7258, 94669, 93138001, 42940801, 42967001, 42967002, 42967003, 42991801, 31007-

02, 31007-03, 5045001-15). 

Table D1 – Product Chemistry of Lithium Hypochlorite 

Guideline 

No. Physical and Chemical Properties Lithium hypochlorite

830.1550 Product identity and composition Refer to Table 3. 

830.1600 Description of materials used to produce 

the product 

Confidential Business Information (CBI). 

830.1620 Description of production process CBI. 

830.1650 Description of Formulation Process CBI. 

830.1670 Discussion of Formation of Impurities CBI. 

830.1700 Preliminary analysis CBI. 

830.1750 Certified limits CBI. 

830.1800 Enforcement analytical method FMC Lithium Division method 05-LTM-564. 

830.1900 Submittal of samples CBI. 

830.6302 Color 

830.6303 Physical State Granular solid. 

830.6304 Odor Odorless or with slight odor of chlorine. 

830.6313 Stability to normal and elevated 

temperature, metals/metal ions 

Stable and retains 90% of available chlorine when stored in 

fiber containers with aluminum overwrap at 75F (23.88°C) and 

75% relative humidity for 4 months. 

830.6314 Oxidation/Reduction Lithium hypochlorite with 39% available chlorine has some 

oxidizing effect. 

Strong Oxidizing Agent. 

Oxidizer. 

Lithium hypochlorite is a powerful oxidizing agent, 

particularly in the presence of water or at higher temperature as 

it decomposes to release oxygen and chlorine gases. Forms 

highly explosive NCl3 on contact with urea or ammonia. When 

heated or on contact with acids, it produces highly toxic fumes 

of chlorine gas. 

830.6315 Flammability Not applicable. Noncombustible. 

830.6316 Explodability Not explodable. 

830.6320 Corrosion Characteristic Corrosive. 

830.7000 pH 

9.9 (available Cl2 - 100 ppm) in distilled water at 25°C. 

10.3 (available Cl2 - 200 ppm) in distilled water at 25°C. 

10.7 (available Cl2 - 300 ppm) in distilled water at 25°C. 

11 at 25 °C (1% Solution). 

830.7050 UV/Visible Absorption Not reported. 

830.7100 Viscosity Not applicable. 

830.7200 Melting point 135 °C with decomposition. 

830.7220 Boiling point Not applicable. 

830.7300 Density 0.531 g/cm3 (20 °C). 
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Guideline 

No. Physical and Chemical Properties Lithium hypochlorite

Bulk Density: 58 lbs/ft3. 

830.7370 Dissociation Constant 

3.2 x 10-8 (of HOCl in aqueous solution). 

Lithium hypochlorite dissociates completely on dissolving in 

water, and is soluble to 43 grams product to 100 grams water. 

830.7550 Partition coefficient (n-octanol/water) Not applicable. 

830.7840 Solubility in water 43% by weight at 25°C. 430 g/L. 

830.7860 Solubility in organic solvents Product should be mixed only with water. 

830.7950 Vapor pressure Not applicable. 

6.63 x 10-17 mm Hg (EPI Suite v4.1). 

atm-m3/mol = atmosphere cubic meter per mole; oC = degrees Celsius; mg/L = milligrams per liter; mmHg = 

millimeters of mercury.